1. Field of the Invention
The present invention relates to a liquid-crystal display element suitable for a thin display having a pair of thin glass substrates, and to a method for manufacturing such a liquid-crystal display element.
2. Description about the Related Art
In liquid-crystal display elements used in displays for notebook personal computers and portable information terminals, in order to achieve a thin and light design, one essential element is to make the thickness of the pair of glass substrates of the liquid-crystal display element thin.
In order to make the thickness of the pair of glass substrates thin, as disclosed, for example, in the Japanese Unexamined Patent Publication (KOKAI) No. 5-61011, a liquid-crystal display element is formed by the process illustrated in FIG. 6.
Specifically, after affixing together an array substrate 10 and an opposing substrate 11, which are the pair of glass substrates, at least one of the array substrate 10 and the opposing substrate 11 is polished (steps 501 and 502). Next, after cutting the array substrate 10 and the opposing substrate 11, a liquid crystal is injected between the array substrate 10 and the opposing substrate 11. The resulting structure is sealed, and a polarizer is affixed thereto (steps 503 to 506).
The grain diameter used as a polishing material for polishing at least one of the array substrate 10 and the opposing substrate 11 is approximately 1 to 2 xcexcm.
For this reason, the polishing material is intruded into the space (5 to 6 xcexcm) between the array substrate 10 and the opposing substrate 11, thereby causing failures due to this foreign matter, which lowers the display quality and yield of the liquid-crystal display elements.
Given the above, in order to solve the above-noted problem, in the Japanese Unexamined Patent Publications (KOKAI) Nos. 5-249422, 5-249423, and 4-116619, for example, the is disclosure of technology wherein, as shown in FIG. 7, when adhering together the array substrate and the opposing substrate, the liquid crystal injection region of the liquid-crystal display element area is surrounded by a seal 12, and further wherein the entire liquid-crystal display element area is surrounded by an outer peripheral seal 18, after which the hole is sealed by a hole sealant 20.
In this type of technology, because the overall liquid-crystal display element area is surrounded by an outer peripheral seal 18, in the above-noted case of performing polishing, intrusion of foreign matter into the space (5 to 60 xcexcm) between the array substrate 10 and the opposing substrate 11 is prevented.
In the above-noted technology, however, in a method of surrounding the overall liquid-crystal display element area with the outer peripheral seal 18, when cutting apart the individual liquid-crystal display elements the outer peripheral shield 18 is also cut.
For this reason, because the stress on the pair of glass substrates is different between a part at which the outer peripheral seal 18 is cut and a part at which the outer peripheral seal 18 is not cut, improper cutting results when scribing and breaking the substrates.
When the above-noted types of problems occur, polishing material intrudes between the space between the outer peripheral seal 18 and the pair of glass substrates, thereby contaminating the manufacturing apparatus.
If the manufacturing apparatus becomes contaminated in this manner, polishing material can intrude into the liquid-crystal display element when the liquid crystal is injected, leading to improper liquid crystal orientation and faulty operation, such as the proper voltage not being applied across the liquid crystal, thereby causing a display failure and a drop in yield.
Accordingly, it is an object of the present invention, in consideration of the above-noted problems, to provide a liquid-crystal display element and a method for manufacturing a liquid-crystal display element wherein the achievement of thinness is facilitated and it is possible to achieve an improvement in yield and quality.
In order to achieve the above-noted object, the present invention has the following basic technical constitution.
Specifically, in a liquid-crystal display element according to one aspect of the present invention, an array substrate on which a plurality of liquid-crystal injection areas are arranged and each liquid-crystal injection area is surrounded by a seal having an aperture and the overall liquid-crystal injection areas being surrounded by an outer peripheral seal having an aperture, and an opposing substrate are adhered together, the aperture of the outer peripheral seal being sealed by a hole sealant, and a surface of at least one of the array substrate and the opposing substrate being polished with a polishing material, and thereafter, an end portion of at least either one of the array substrate and the opposing substrate being polished with end polishing operation so as to remove residual polishing material therefrom, after which cutting plurality of liquid-crystal injection areas along lines as formed between the opposite the aperture holes so as to separate individual liquid crystal injection areas.
In this aspect of the present invention, a plurality of the apertures of the outer peripheral seal are provided along the outer peripheral seal and at crossing points each being formed between the outer peripheral seal and a line along which the individual liquid-crystal injection areas are cut apart.
In this aspect of the present invention, it is possible to inject liquid crystal into each individual injection area, seal the areas, and adhere polarizers after the individual liquid crystal injection areas are separated.
The seal and outer peripheral seals can be made of an epoxy resin, the hole sealant can be a UV-curing acrylic resin, and the polishing material can be an alumina polishing material.
A method for manufacturing a liquid-crystal display element according to another aspect of the present invention comprising, a first step of forming a plurality of liquid-crystal injection areas surrounded with a seal on an array substrate, a second step of adhering the array substrate on which overall the liquid-crystal injection areas being surrounded by an outer peripheral seal having an aperture and an opposing substrate, a third step of sealing the aperture of the outer peripheral seal using a hole sealant, a fourth step of polishing a surface of at least one of the array substrate and the opposing substrate using a polishing material, a fifth step of polishing an end surface of at least one of the array substrate and the opposing substrate, using a polishing material and removing the polishing material, and a sixth step of cutting the liquid-crystal injection areas along a virtual lines each formed between the apertures each provided on two of the outer peripheral seals, respectively, and each of the outer peripheral seals being oppositely arranged to each other.
The second step thereabout can include a seventh step of providing a plurality of the apertures being provided along each one of the outer peripheral seals and at crossing points each being formed between the outer peripheral seal and a virtual line along which the individual liquid-crystal injection areas would thereafter be cut apart.
The sixth step can include an eighth step of injecting liquid crystal into each liquid-crystal injection area, sealing the hole, and adhering a polarizer.
The first step can include a ninth step of forming a seal using an epoxy resin, the second step can include a tenth step of forming an outer peripheral seal using an epoxy resin, and the third step can include an eleventh step of forming a hole sealant with a UV-curing acrylic resin.
The fourth step can include a twelfth step of performing polishing using an alumina polishing material, a thirteenth step of performing lapping, and a fourteenth step of performing final polishing, and the fifth step can include a fifteenth step of chamfering the polished end surface.
In a liquid-crystal display element and a method for manufacturing a liquid-crystal display element according to the present invention, an array substrate on which a plurality of liquid-crystal injection areas surrounded with a seal and the overall liquid-crystal injection areas being surrounded by an outer peripheral seal are provided and an opposing substrate are adhered together, the aperture of the outer peripheral seal being sealed by a hole sealant, and the surface of at least one of a surface of the array substrate and the opposing substrate being polished with a polishing material and further an end portion thereof is also polished so that the polishing material is removed, after which cutting along the aperture is done to separate the individual liquid-crystal injection areas.